What comes next is an open question: The Obama administration has convened an independent panel to review NASA's plans for manned spaceflight, and until that committee delivers its findings next month, it remains unclear what targets (the moon? Mars? a nearby asteroid?) the U.S. will set or what hardware it will use to get there.

Bolden, 62, told the AP that he would be "incredibly disappointed if we have not at least reached Mars" in his lifetime. Bolden spoke more of Mars than the moon but "didn't rule out using the moon as a stepping-stone" to the Red Planet or even farther afield, according to the AP. Such a philosophy would likely please the many high-profile space advocates, such as Edwin "Buzz" Aldrin, who bemoan focusing on the moon, reached by astronauts 40 years ago, as a target for the future.

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